Acids Zirconium isopropoxide

This work involves the modification of silica-zirconia (33 mol% zirconia) via sulphation and phosphation processes and a comparison of the resultant acidic properties. Mixed oxides were prepared by the sol-gel method which allowed homogeneous mixing of the two component oxides at room temperature. Procedure involved pre-hydrolysis of TEOS with nitric acid and water followed by the addition of zirconium isopropoxide. S Zr and P Zr ratios of 0.20 1, 0.25 1, and 0.30 1 were employed whereby the addition... 

Phosphate and sulphate modifiers were incorporated by the addition of appropriate amounts of 0.01 M sulphuric or phosphoric acid to a pre-calcined aerogel followed by further calcination at 873 K. Samples are labeled as X-SiZr (y) where X refers to either sulphated (S) or phosphated (P) samples, and y refers to the mole ratio of sulphate/phosphate relative to zirconium in the preparation method. For comparison purposes, samples of zirconia and sulphated zirconia were also prepared. This was achieved via precipitation from zirconium isopropoxide (Aldrich 70 wt.%). The same H2O Zr propanol ratios were employed as used during the preparation of the mixed oxides. A sulphated zirconia, prepared by the use of sulphuric acid as hydrolysis catalyst was prepared for comparative purposes and had a nominal S Zr ratio of 0.30 1. A further sample was prepared where segregation of components was induced by thermal treatment by calcination at 1373 K for 6 h.of the non-treated SiZr (0)... 

The reactions of zirconium isopropoxide with fatty acids (caproic, lauric, palmitic, and stearic) were found to be similar to those of titanium isopropoxide, except that the tris-product, Zr(OPr )(OOCR)3 was more stable than the titanium analogue and could be isolated at lower temperatures in 1 3 molar reactions. However, it reacted very slowly with a further mole of the acid, and the tetracarboxylate so formed reacted readily with Zr(OPr )(OOCR)3 yielding the basic carboxylate (RC00)6Zr20 ... 

Trialkylaluminums, 204 Trichloroisopropoxytitanium, 300 Triisobutylaluminum, 205 Trimethylaluminum, 205 Trityl perchlorate, 339 Trityl tetrafluoroborate, 301 Zinc bromide, 349 Zinc chloride, 44, 108, 181, 190, 349 Zinc iodide, 88, 112, 280, 349, 350 Zirconium(IV) acetylacetonate, 351 Zirconium(IV) chloride, 16 Zirconium(IV) isopropoxide, 311 Other Organic and Inorganic Acids Acetic acid, 45 Benzoic acid, 312 Camphor-10-sulfonic acid, 62, 64 Formic acid, 137... 

Pal and Kapoor74 have studied the reactions of isopropoxides of aluminum, titanium and zirconium with benzo- and phenylaceto-hydroxamic adds in anhydrous benzene. Solid products of the types Al(OPr )3 L and M(OPri)4 L (where M = Ti or Zr and L is the hydroxamic acid) have been isolated all the aluminum and zirconium products are white in colour whereas titanium ones are yellow. The mixed isopropoxide hydroxamates interchange their isopropoxy group with r-but-oxy groups, yielding r-butoxide products. 

Aluminum isopropoxide has been described in a 1958 US patent (39) as an MPV reductant to selectively convert the 7-ethylenedioxy derivative of a substituted dodecahydrophenanthrene to its 4b-methyl-7-ethylenedioxy-l,2,3,4,4a.4b,5,6,7,8,10,10a-dodecahydrophenanthrene-4-ol-l-one. The MPV reduction of pyrimidin-2(lH)-ones to the corresponding 3,4-dihydro- pyrimidin-2(lH)-ones has been accomplished with zirconium tetraalkoxide and with AIP, although the Zr-alkoxide was more effective (40). Aluminum isopropoxide has proven useful in the reduction of 5P-hydroxy-8-oxo-l,4,4aa,5,8,8aa-hexahydronapthalene-lp-carboxylic acid to a preciusor used in the synthesis of reserpine and related comnpoimds (41,42). 

The following chemicals have been used Almninium isopropoxide, 98+ (Aldrich), cerium (III) 2-ethyUiexanoate, 49% in 2-ethyUiexanoic acid (Alfa Aesar), copper (II) 2-ethyUiexanoate, 98% (Alfa Aesar), platinum (II) acetyl-acetonate, 97% (Alfa Aesar), zinc 2-ethyIhexanoate, 99% (Alfa Aesar) and zirconium (IV) n-propoxide, 70% w/w in n-propanol (Alfa Aesar)... 

Pb(Zr,Ti)03 Lead (II) acetate, titanium isopropoxide, zirconium n-propoxide Glacial acetic acid, ethylene glycol 4... 

It was possible to paepare ZrTi04 powders from zirconium n-propoxide and titanium isopropoxide, at a Zr Ti molar ratio of 1 1, in propanol, with and without addition of nitric acid using the sol-gel process at ambient temperature (20 °C) and low thermal treatment. 

In the formation of lead zirconate titanate (PZT) nanorods, lead acetate, titanium isopropoxide, zirconium w-propoxide, glacial acetic acid, lactic acid, ethylene glycol, and glycerol were used for the PZT sols. The template membranes used for the growth of nanorods were track-etched hydrophilic polycarbonate (PC) with pore diameters of 100 and 200 mn and a thickness of 10 /xm. The PC membrane attached to Al cathode is placed... 

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